The present invention relates to mechanical engineering, and more particularly to positive-displacement-action machines, and may be used as an engine, a pump, a compressor or a metering device.
Known in the art is a positive-displacement sphere-shaped rotor machine comprising a casing consisting of two interconnected parts, in a spherical cavity of the casing three rotors are disposed that define four chambers. A central rotor is connected from each side by means of a diametrical hinge to a sector rotor in the form of a ball sector, made integral with a shaft. The axes of rotation of the sector rotors are disposed at a certain angle to each other and intersect the axes of the diametrical hinges in the center of the spherical cavity. The axes of the diametrical hinges are perpendicular to each other. The rotors adjoin with their peripheral surfaces the spherical cavity of the machine casing in which four inlet-outlet ducts are disposed (JP No. 47-44565, PCT/SU89/00133).
The known machine is disadvantageous in that the thickness of the sector rotor in the shaft region is small. As a result, the shaft diameter and the size of main bearings are limited, the zone of total overlapping of the spherical cavity of the casing by the spherical surface of the rotor is insufficiently developed, and, as a consequence, the packing devices bordering the hot zone of the working chambers are complicated and ineffective. Locating the inlet-outlet ducts near the bearing units mutually limits their effectiveness. A relatively small thickness of the shafts and sector rotors makes the heat removal therefrom difficult, and this brings about their considerable calorific intensity. The presence of a large dynamically unbalanced mass on the periphery of the central rotor leads to the origination of considerable internal stresses and deformations at high rotation speeds of the rotors. The above-said disadvantages limit the performance and reliability of the machine.
A machine is known, wherein the semi-axles of diametrical hinges are removable and provided with grooves, and sector rotors are provided with projections mating the latter, the central rotor has a bore, and the sealing is made removable and is disposed in the bore (SU No. 877129).
This machine is disadvantageous in that the semi-axles of the diametrical hinges are disposed freely, whereby the speed of rotation of the rotors is limited because of high centrifugal loads of the freely disposed semi-axles acting on the sphere-forming surface of the machine.
It is an object of the present invention to increase the performance and prolong the service life of the positive-displacement sphere-shaped rotor machine.
This object is accomplished by the provision of a positive-displacement sphere-shaped rotor machine comprising a casing consisting of two interconnected parts, in a spherical cavity of the casing three rotors being disposed that define four working chambers, a central rotor connected from each side by means of a diametrical hinge to a sector rotor in the form of a ball sector, made integral with a shaft, the axes of rotation of the sector rotors being disposed at a certain angle to each other and intersecting the axes of the diametrical hinges in the center of the spherical cavity, the axes of the diametrical hinges being perpendicular to each other, the rotors adjoining with their peripheral surfaces the spherical cavity of the machine casing in which four inlet-outlet ducts are disposed, in which machine, according to the invention, chamber-forming radial surfaces of the sector rotors are formed by two and more planes or by a curvilinear or plano-curvilinear surface which provides an increase of the sector-forming angle from the diametrical hinge to the peripheral spherical surface, measured between the axis of rotation of the sector rotor and a straight line connecting the center of the sphere with a point on the chamber-forming surface of the sector rotor, and the chamber-forming surface of the central rotor repeats the form of the sector rotor surface corresponding thereto.
The above-described structural embodiment makes it possible to increase substantially the performance and service life of the machine.
The invention will be better understood from the following description of particular embodiments thereof with reference to the accompanying drawings.